The present invention relates to an arrangement for unloading and loading x-ray sheet film cassettes of standardized and at the same time different sizes of their flat sides, which can be designed for receiving different sheet film sorts and reloadable with respective sheet film sorts.
Arrangements of the abovementioned general type are known in the art. Such an arrangement has a light-tightly closeable shaft for receiving a cassette, transporting means for insertion and withdrawal of the cassette, means for positioning of the cassette at a cassette corner which is identical for all cassettes, and mechanically-electronic comparison device for determining the format of a cassette, an opening device for the cassette, means for film withdrawal from the cassette and insertion of a new film into the cassette.
An arrangement of this type is known in different variants, and disclosed for example in the Patent Document EP-OS No. 0,052,159 A1. In this arrangement it is however not possible to automatically recognize in mechanical or mechanically-electronic means the film cassettes of the same size which are to be loaded with different film sorts, and to load with a film not only of the correct size but also of the correct film sort.
Another similar arrangement in which the cassettes have different codes which are sensible by different electrical or magnetic electro-optical means in dependence on their size and the film sort contained in them, are disclosed for example in the Patent Documents DE-OS No. 3,533,953, DE-OS No. 3,533,954 or DE-OS No. 3,609,527. When different film formats and film sorts are available, many different codes and respectively many evaluating devices for many different codes are required. Thereby it is not possible for a user to perform the coding itself in correspondence with its specific requirements.